Combustion apparatus

ABSTRACT

In a gas turbine, the transition pieces of the combustor baskets are retained in assembled relation, and the joint between adjacent transition pieces sealed by means of seal frames, attached to the transition pieces, and seal members which slidably engage adjacent seal frames. The structure reduces the tendency of the side walls of the transition pieces to buckle and simplifies the assembling of the transition pieces.

United States Patent Hugoson Apr. 25, 1972 [54] COMBUSTION APPARATUS[72] inventor: Birger O. Hugoson, Wallingford, Pa.

[73] Assignee: Westinghouse Electric Corporation, Pittsburgh, Pa.

[22] Filed: Nov. 13, 1970 [21] Appl.No.: 89,396

i521 L'.S. Cl 60/3931, (JO/39.37 [51] Int. Cl. 1 i 1 t ..F02c 3/00 [58]Field ofSearch ..60/39.3l,39.37,39.69

[56] References Cited UNITED STATES PATENTS 2,608,057 8/1952 Boyd..60/39.37

2,702,454 2/1955 Brown ..60/39.3l 2,748,567 6/1956 Daugherty ..60/39.373,018,624 1/1962 Bonsall ..60/39.37

Primary Examiner- Douglas Hart Atl0rneyA. T. Stratton, F, P. Lyle and F,Cristiano, Jr,

[57] ABSTRACT In a gas turbine, the transition pieces ofthe combustorbaskets are retained in assembled relation, and the joint between adjacent transition pieces sealed by means of seal frames, uttached to thetransition pieces, and seal members which slidably engage adjacent sealframes. The structure reduces the tendency of the side walls of thetransition pieces to buckle and simplifies the assembling of thetransition pieces.

10 Claims, 5 Drawing Figures PATENTED APR 2 5 I972 SHEET 2 BF 2 FIG. 4

COMBUSTION APPARATUS BACKGROUND OF THE INVENTION This invention relates,generally, to combustion apparatus and, more particularly, to combustionapparatus for a gas turbine power plant.

Under certain circumstances it becomes desirable to utilize a largenumber of relatively small combustor baskets in a gas turbine instead ofa small number of relatively large baskets. One consideration is cost oftesting and availability of testing facilitates. Another, is themechanical strength of the different sizes of baskets and transitionpieces. When the number of baskets utilized in a turbine of a certainsize is increased, the wedge shaped open space between baskets isreduced, creating a situation where the sides of the transition piecesare close to each other and having an extended area of flat side walls.When conventional seal methods are used between the transition piecesand the first stage turbine stator ring, the side walls are in danger ofbuckling since they are exposed to the pressure drop across thecombustor, and the temperature gradient in the walls works in the samedirection as the pressure load. This invention provides a gas turbinecombustor transition structure that reduces the tendency of the sidewalls to buckle, and, at the same time, simplifies the assembling of thetransition pieces in the turbine.

BRIEF SUMMARY OF THE INVENTION In accordance with one embodiment of theinvention, flanged seal frames are secured to adjacent sides of gasturbine combustor transition pieces at their outlet ends. Inturnedflanges on a seal member, which is generally like an I-beam in shape,slidably engage the flanges on adjacent seal frames to retain thetransition pieces in assembled relation. The web portion of the sealmember is disposed between adjacent seal frames to close 01f adjacentopenings in sides of the transition pieces. The seal member is exposedto substantially the same pressure and temperature on both sides,thereby reducing the buckling tendency.

BRIEF DESCRIPTION OF THE DRAWING For a better understanding of thenature of the invention, reference may be had to the following detaileddescription, taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is an isometric view of portions of adjacent combustor basketsand seal members embodying principal features ofthe invention;

F IG. 2 is an isometric view of one of the seal members utilized forretaining adjacent transition pieces of combustor baskets in assembledrelation;

FIG. 3 is an enlarged fragmentary view of a portion of the structureshown in FIG. 1;

FIG. 4 is a view, in elevation, of half of an annular array of combustorbaskets for a gas turbine assembled in closely spaced relation, and

FIG. 5 is an isometric view of a modified seal member, a portion beingbroken away for clearness.

DESCRIPTION OF PREFERRED EMBODIMENT Referring to the drawing,particularly FIG. I, the structure shown therein comprises a portion ofa combustor basket which is of the canister type suitable for supplyinga hot motivating fluid to the rotor of a gas turbine power plant in amanner well known in the art. The portion of the combustor basket 10shown includes a generally cylindrical intermediate section 12 and atransition piece 14 having a generally cylindrical upstream end portion16 joined to the intermediate section 12, and a downstream portion 18that progressively changes in contour from circular cross section as thejointure with the cylindrical intermediate section 12 to arcuate crosssection at its outlet end portion 20.

As shown more clearly in FIG. 4, the arcuate extent of the outlet 20 issuch that, jointly with the outlets of the other combustor baskets, acomplete annulus is provided for admitting the hot products ofcombustion from the combustor baskets 10 to the blades of a gas turbine(not shown), thereby providing full peripheral admission of motivatinggases to the turbine. The arcuate ends of the transition piece 18 may bestrengthened by outwardly extending flanges 22 secured to the ends ofthe transition piece.

As explained hereinbefore, when a relatively large number of combustorbaskets are provided for a gas turbine, the wedge shaped open spacebetween baskets is reduced, approaching a situation where the sides ofthe transition pieces are very close to each other and having anextended area of flat side walls. Heretofore, when conventional sealmethods between the transition pieces and the first stage stator ring ofa turbine were utilized, the side walls were in danger of buckling sincethey were exposed to the pressure drop across the combustor. Also, thetemperature gradient in each side wall was working in the same directionas the pressure load on the side wall.

In order to overcome this buckling problem, a portion of each side wallof each transition piece 18 is cut away to provide openings 24 in theside walls of the transition pieces. Each opening 24 is disposed withina seal frame 26 secured to the side wall of the transition piece 18.Each seal frame 26 comprises two angle members 28 each having one leg 30attached to the side wall of a transition piece 18 and the other leg 32providing an inwardly extending flange spaced from the transition piece.The end of the leg 30 disposed nearest the outlet 20 of thetransitionpiece is secured directly to the transition piece, as bywelding, and the other end of the leg 30 is spaced from and attached tothe transition piece by means of a generally triangular shaped gussetplate 34. The space between the ends of the angle members 28 which arespaced from the transition piece 18 is closed by a gusset plate 36having a concave edge secured to the transition piece 18, as by welding.

In order to retain the transition pieces 18in assembled relation, and toclose off adjacent openings 24 in the transition pieces, a seal member38 is provided. As shown more clearly in FIG. 2, the seal member 38 isgenerally like an I-beam in shape having a web portion 40 and flanges 42formed integrally with the web 40. The edges of each flange 42 areturned inwardly to form inturned flanges 44 spaced from the web 40.

As shown more clearly in FIG. 3, the flanges 44 on the seal member 38slidably engage the flanges 32 on adjacent seal frames 28 when the web40 of the seal member is moved into position between two adjacent sealframes. Seal strips 46 are secured to the web 40, as by welding, toengage the gusset plates 36 when the seal member 38 is installed.

In this manner adjacent openings 24 in adjacent transition pieces 18 areclosed off by the web 40 of the seal member 38 and the motivating fluidis prevented from escaping around the seal frame 28 by the gusset plates34, 36 and the seal strips 46. The transition pieces 18 are retained inassembled relation by the flanges 32 on the seal frames 28 which areengaged by the inturned flanges 44 on the seal member 38. The clearancebetween adjacent transition pieces makes allowance for circumferentialgrowth of the transition pieces. Since the seal member 38 betweenadjacent transition pieces is exposed to substantially the same pressureand temperature on both sides, the buckling tendency is reduced.

In the modification of the invention shown in FIG. 5, the web portion ofthe seal member 38a comprises two plates 40a and 40b secured together inspaced relation to permit air circulation between the plates. As shown,oppositely disposed indentations 48 on the plates may be securedtogether, as by spot welding. The ends of the plates 40a and 40b may besecured together, as by welding. The edges of the plates have inturnedflanges 440 which function in the same manner as the flanges 44 toslidably engage the flanges 32 on adjacent seal frames 28 when the sealmember 38a is installed. In this manner air is permitted to circulatebetween adjacent transition pieces, thereby aiding in cooling thetransition pieces.

From the foregoing description it is apparent that the inventionprovides an improved combustor transition piece arrangement and sealmembers which simplify the assembling of the transition pieces ofcombustor baskets in a gas turbine. The seal frames and seal membersretain the transition pieces in assembled relation and preventescapement of the motivating fluid from the transition pieces.Furthermore, tendency of the transition pieces and the seal members tobuckle is reduced.

Iclaim: 1. ln combustion apparatus for a gas turbine power plant, incombination,

an annular array of combustor baskets having transition pieces disposedin closely spaced relation, flanged seal frames secured to adjacentsides of the transition pieces at their outlet ends, and a seal memberhaving inturned flanges slidably engaging the flanges on adjacent sealframes to retain the transition pieces in assembled relation. 2. Thecombination defined in claim 1, wherein each seal frame comprises twoangle members and gusset plates secured to the transition pieces. 3. Thecombination defined in claim 2, wherein one end of each of the anglemembers is secured directly to a transition piece and the other end isspaced from the transition piece by a triangular shaped gusset plate.

4. The combination defined in claim 3, including a gusset plate disposedat the ends of the angle members spaced from the transition piece andhaving a concave edge secured to the transition piece.

5. The combination defined in claim 2, wherein each seal member isgenerally like an I-beam in shape with a web portion and inturnedflanges slidably engaging the angle members of two adjacent seal frames.

6. The combination defined in claim 5, wherein the web portion of eachseal member is disposed between adjacent sides of two transition pieces.

7. The combination defined in claim 6, wherein adjacent sides of thetransition pieces have openings therein within the seal frames tocommunicate with each other, and the web portions of the seal membersclose off said openings.

8. The combination defined in claim 4, including seal strips on the sealmembers engaging the gusset plates having concave edges.

9. The combination defined in claim 5, wherein the web portion of eachseal member comprises two plates secured together in spaced relation.

10. The combination defined in claim 9, wherein the plates of the webportion are spaced apart by oppositely disposed indentations in theplates and are welded together at said indentations.

1. In combustion apparatus for a gas turbine power plant, incombination, an annular array of combustor baskets having transitionpieces disposed in closely spaced relation, flanged seal frames securedto adjacent sides of the transition pieces at their outlet ends, and aseal member having inturned flanges slidably engaging the flanges onadjacent seal frames to retain the transition pieces in assembledrelation.
 2. The combination defined in claim 1, wherein each seal framecomprises two angle members and gusset plates secured to the transitionpieces.
 3. The combination defined in claim 2, wherein one end of eachof the angle members is secured directly to a transition piece and theother end is spaced from the transition piece by a triangular shapedgusset plate.
 4. The combination defined in claim 3, including a gussetplate disposed at the ends of the angle members spaced from thetransition piece and having a concave edge secured to the transitionpiece.
 5. The combination defined in claim 2, wherein each seal memberis generally like an I-beam in shape with a web portion and inturnedflanges slidably engaging the angle members of two adjacent seal frames.6. The combination defined in claim 5, wherein the web portion of eachseal member is disposed between adjacent sides of two transition pieces.7. The combination defined in claim 6, wherein adjacent sides of thetransition pieces have openings therein within the seal frames tocommunicate with each other, and the web portions of the seal membersclose off said openings.
 8. The combination defined in claim 4,including seal strips on the seal members engaging the gusset plateshaving concave edges.
 9. The combination defined in claim 5, wherein theweb portion of each seal member comprises two plates secured together inspaced relation.
 10. The combination defined in claim 9, wherein theplates of the web portion are spaced apart by oppositely disposedindentations in the plates and are welded together at said indentations.